Pipe wrapping machine



P 1969 L. STUART, JR, ETAL 3,470,057

PIPE WRAPPING MACHINE 5 Sheets-Sheet 1 Filed July 15. 1966 INVENTURS LINDEN $7115.97- BY 5960* F CuQT/s TFOPNEXS Sept. 30, 1969 STUART, JR. ETAL 3,470,057

PIPE WRAPPING MACHINE Filed July 15, 1966 5 Sheets-Sheet 2 INVEN'IURS Z/IYOEN STU/9R7; c/ BY FfAIYk F CuQTIS P 1969 Q L. STUART, JR.. ETAL I 3,470,057

PIPE WRAPPING MACHINE 5 Sheets-Sheet Filed July 15. 1966 OHII HHHN INVEN'IORS LINDEN 6 7m United States Patent PIPE WRAPPING MACHINE Linden Stuart, Jr., Bedminster, and Frank F. Curtis, South Plainfield, N.J., assignors to Stuart Steel Protection C0rp., Somerset, N.J., a corporation of Delaware Filed July 15, 1966, Ser. No. 565,481 Int. Cl. B31c 11/04, 3/00 U.S. Cl. 156392 11 Claims ABSTRACT OF THE DISCLOSURE A portable, manually operated, heated, pipe wrapping machine for wrapping strips of protective material about pipes in the field.

This invention relates to a pipe wrapping machine. More particularly, this invention relates to a pipe wrapping machine for wrapping a protective strip of material about a pipe. Still more particularly, this invention relates to a portable pipe wrapping machine for wrapping a protective strip of material about a joint between two pipes in the field.

Pipe wrapping machines have been known which have been utilized to wrap various types of protective material about pipes either before shipment or in the field before or after placement. The pipe wrapping machines which have heretofore been used in the field have generally coated the pipes with a coating material and then applied the protective material over the coating so as to secure the protective material to the pipe. Further, these field machines have usually been utilized to cover the entire pipeline formed by a series of interconnected pipe sections.

In addition, the pipe wrapping machines heretofore used in the field have been of great bulk and weight and in several cases have been propelled by power means because of the size and weight.

Accordingly, it is an object of this invention to provide a pipe wrapping machine for wrapping protective material about exposed end surfaces of prewrapped pipes.

It is another object of this invention to provide a pipe wrapping machine which is portable.

It is another object of this invention to provide a pipe wrapping machine which is manually operated.

It is another object of this invention to provide a pipe wrapping machine for wrapping and adhesively securing a preformed protective material about a weld joint between two pipe sections.

It is another object of this invention to provide a pipe wrapping machine with an integrated heating means for adhesively securing a preformed strip of protective material about a weld joint formed between a pair of precoated pipe sections.

It is another object of this invention to provide a pipe wrapping machine which is automatically adjustable for use with pipes within a range of pipe diameter sizes.

It is another object of this invention to provide a pipe wrapping machine which' is adjustable for different pipe diameters while constantly maintaining a wrapper applying force on the wrapper being applied to a pipe joint.

Generally, the invention provides a portable pipe wrapping machine which comprises a frame which is shaped to envelop a pipe, a locking means to secure the frame around the pipe, means for rotatably supporting the frame concentrically on the pipe, a reel assembly for "ice feeding a strip of wrapping material from a roll of such to the pipe, a heater assembly for heating the strip to an adhesive state before application to the pipe and a pressure applying assembly for pressing the heated strip against the pipe to effect an adhesive engagement.

The wrapping material is a preformed strip having an outer layer of felt or other suitable backing sheet and an inner layer comprising thermoplastic material which is heated by the heater assembly to an adhesive state for adhesion to the pipe.

The machine is manually positioned on the pipe to be wrapped adjacent the weld joint and orbited around the pipe in a direction to pay out the wrapping material in a helical manner in the region adjacent the weld. Since the inner layer of the wrapping material is heated to an adhesive state and pressed against the pipe while in such a state, the exposed portions of the pipe sections adjacent the weld are securely and effectively wrapped.

These and other objects and advantages of the invention will become more apparent from the following detailed description and appended claims taken in conjunction with the accompanying drawings in which:

FIG. 1 illustrates a perspective view of a pipe wrapping machine of the invention in place over a welded joint between two pipe sections;

FIG. 2 illustrates a perspective view of the pipe wrapping machine of FIG. 1 rotated about with reference to the position shown in FIG. 1;

FIG. 3 illustrates a perspective view of the pipe wrapping machine of FIG. 1 rotated about 270 with reference to the position shown in FIG. 1;

FIG. 4 illustrates an end view of the pipe wrapping machine immediately before positioning about a pipe;

FIG. 5 illustrates an end view of the pipe wrapping machine immediately after positioning about a pipe;

FIG. 6 illustrates a view of the heater assembly for the preformed strip of protective material on the pipe wrapping machine;

FIG. 7 illustrates a view of the relative positions of the material feeding spool, the pressure applying rollers and the heater assembly;

FIG. 8 illustrates a view taken on line 88 of FIG. 7;

FIG. 9 illustrates a view of the heater taken on line 9-9 of FIG. 1;

FIG. 10 illustrates a schematic view of an exposed weld joint between a pair of pipe sections; and

FIG. 11 illustrates a schematic view of a weld joint protectively covered by the pipe wrapping machine of the invention. I

Referring to FIGS. 1 to 3, 6 and 7, the pipe wrapping machine 15 which is of a compact size and of relatively light weight is positioned manually or otherwise over the weld joint formed between abutting ends of a pair of pipe sections 16a and 16b of the pipe indicated generally by 16 which are generally of cylindrical shape, for example, of 6 to 12 inch diameter and provide a pipe for use as gas lines, water lines, petroleum pipelines, and the like. The machine 15 is suitably retained on and orbited around the pipe 16 in a helical fashion so as to wrap and secure a preformed strip of protective material around the weld joint.

The pipe sections 16a and 16b which are jointed together, as by a butt weld, are generally provided at the factory with a wrapping of felt over hot-applied tar or asphalt. Upon delivery of the individual prewrapped pipes to the installation site, a portion of the felt and tar is removed from each end leaving a zone of exposed pipe which, in the case of a 6 inch pipe, for example, may be about 1 foot in length. The exposed ends of two pipe sections are then brought together in alignment and butt welded together.

The pipe wrapping machine 15 has a pair of aligned U-shaped spaced frame members 17 fixed with respect to each other by a suitable number of cross bars 18, for example, two cross bars, which are secured to each of the frame members 17 in any suitable manner. For example, each cross bar 18 has threaded end portions 19 which project through suitable apertures in the respective frame members for receiving threaded locking nuts 20 thereon. The frame members 17 are dimensioned so that the mouth of the cavity formed by virtue of the U-shape is of sufficient size to pass over the pipes to be Wrapped.

Each of the frame members 17 and 17 has an adjustable locking means in the form of a releasable arm lock assembly 21 mounted thereon for disposition across the mouth of the cavity formed by the frame members to retain a pipe 16 therein during the wrapping operation. The releasable arm lock assemblies 21 are constructed to be adjustable within a range of pipe diameter sizes so that a single pipe wrapping machine can be mounted on different sized pipes.

Each releasable arm lock assembly 21 includes an arm 22, for example, or fiat shape, which is pivotally mounted at one end on the frame member 17 at 22 and at the other end is provided with a handle 23 having a shank 24 extending from the opposite side of the arm 22 (FIG. 6). In addition, the arm lock assembly 21 includes a second arm 25 which is pivotally mounted at one end on the frame member 17 at the same pivot point 22' as the first arm 22 and which is secured to the first arm 22 by a tension coil spring 26 attached at intermediate points of each arm 22, 25. The tension coil spring 26 allows both arms 22 and 25 to be moved relative to each other depending on the size of the pipe retained within the wrapping machine 15. The second arm 25 is disposed to project across the mouth of the frame member 17 when the arm lock assembly 21 is in a closed position to retain the wrapping machine 15 on the pipes 16. Also, the second arm 25 rotatably mounts a wheel 27 at the free end in angular disposition relative to the frame member 17 so as to enable the wheel 27 to roll about the pipe 16 in a helical path.

In order to lock the arm lock assembly 21 in place, the frame member 17 is provided with a series of suitable apertures 28 in alignment with the path of travel of the shank 24 of the handle 23 so that the shank 24 can be inserted into the aperture corresponding to the size of the pipe 16 upon which the wrapping machine 15 is disposed while imparting a desired tension on the spring 26 for urging the wheel 27 resiliently against the pipe 16.

One of the frame members 17 has wheels 29, 29' rotatably mounted thereon by any suitable adjustable mounting means for contacting the pipe 16 at spaced points so that the points of contact of the wheels 29, 29' and 27 on the pipe section form the apices of a triangle when the wrapping machine 15 is disposed on the pipe 16. The wheels 29, 29' like the wheel 27, are disposed in angular relation to the frame member 17 to travel in a helical path around the pipe 16. Further, the wheels 29, 29 are capable of being adjustably positioned on the frame member 17 depending on the size of the pipe 16 through the mounting means (not shown), for example, by loosening, movement and retightening of threaded securing bolts 30 disposed in suitable slots 31 in the frame member 17.

The other frame member 17' has a wheel 32 (see FIG. 6) similar to wheels 29, 29' which is rotatably mounted in an adjustable manner thereon opposite to the wheel 29. However, the frame member 17' mounts a pressure applying assembly 33 opposite the Wheel 29 of the frame member 17.

The pressure applying assembly 33 (FIG. 8) includes a pair of rollers 34 rotatably mounted on a stub shaft 35 which is secured to the frame member 17' by a suitable pivotally adjustable bracket 36 and a pair of rollers 37 rotatably mounted on a shaft 38 which is mounted in a slightly rockable manner at one end of an apertured bar 39 pivotally secured on the stub shaft 35. The apertured bar 39 is further connected to a cross bar 18 at the other end by a coil spring 40 so as to spring bias the pair of rollers 37 against pipe 16. The coil spring 40 thus allows the pair of rollers 37 to constantly maintain a pressure applying force on the wrapping material being applied to the pipe joint no matter the diametric size of the pipe section and wrapper at a particular point along the pipe joint and no matter the size of pipe within the wrapping machine 15. As above, the rollers 34 and 37 are angularly disposed relative to the frame member 17' so as to ride in a helical path about the pipe 16.

In addition to the pressure applying assembly 33, the frame member 17' also carries a material feeding reel assembly 41 and a heater assembly 42. The reel assembly 41 includes shaft 43 mounted on a suitable bracket 44 in angular disposition to the frame member 17' which rotatably supports a reel 45 having a preformed roll of Wrapping material 46 thereon so that the wrapping material 46 can be helically wound about the pipe 16.

Referring to FIGS. 1 and 9, the heater assembly 42 includes a heating chamber 47 fixedly mounted on a cross rod 48 secured to each of the frame members 17, 17. The heating chamber 47 has a guide plate 49 mounted thereon which defines a confined passageway therewith for passage of the wrapping material 46 therethrough. Further, the heating chamber 47 is heated interiorly by a suitable heat source, for example, a combustible gas which is delivered from a gas supply tank 50 secured to a cross bar 18 by a suitable strap means 51 through a gas line 52 secured to the wrapping machine 15 and heating chamber 47, as by brackets 53. In such a case the heating chamber 47 is opened at an end as well as at the bottom to admit air for effecting combustion with the gas. Also, the gas supply tank 50 is suitably positioned over a plurality of bolts 54 in the frame member 17 for further securement.

The reel assembly 41 and heater assembly 42 are aligned with respect to each other and to the pressure applying assembly 33 so that as the wrapping machine 15 orbits the pipe 16, the preformed wrapping material 46 leaves the reel assembly 41 and passes through the heater assembly 42 before being wrapped about the pipe 16.

The preformed wrapping material 46 utilized with the wrapping machine 15 is composed of an outer layer of asphalt-impregnated or tar-impregnated asbestos felt and an inner layer of glass fiber embedded in a material such as thermoplastic tar or asphalt. The inner layer is sufficiently thermoplastic so as to be rendered adhesive by application of heat.-

In order to facilitate manual handling of the machine 15, a pair of C-shaped handles 55 are secured to the extremities of the frame members 17, 17', as by rivets, welding, etc., so as to enable one to readily transport and rotate the machine 15 thereby.

Referring to FIGS. 4 and 5, in operation, the arm lock assemblies 21 of the wrapping machine 15 are pivoted so that the arms 25 and wheels 27 are moved away from the mouths of the respective frame members 17, 17 a distance to permit passage over the pipe 16. The wrapping machine 15 is then spaced from the exposed weld joint of the abutting pipe sections 16a and 16b and directed over the weld joint manually. As the mouth of the machine 15 envelops the weld joint, the pipe 16 abuts the arms 22 of the arm lock assemblies 21 and pivots the arms 22 so as to pivot the arms 24 and wheels 27 towards the frame members 17, 17' under the influence of the springs 26 until the wheels 27 contact the pipe (as shown in phantom in FIG. 4). The machine 15 further envelops the pipe weld joint until the pipe comes into contact with the wheels 29, 29' of one frame member 17 and the wheel 30 and pressure applying assembly 33 of the other frame member 17'.

Thereafter, the handle 23 of each arm lock assembly 21 is grasped-and the arm 22 pivoted until the shank 24 of the handle 23 is positioned over and inserted into one of the apertures 28 in the respective frame member. This locks the machine 15 firmly to the pipe 16 so that each frame contacts the pipe at three points; the wheels 27 being pressed against the pipe by the tension springs 26.

Referring to FIGS. 6 to 9, when locked on the pipe 16 the wrapping machine 15 is positioned so that the preformed wrapping material 46 will be initially directed over the region of a pipe section which carries the wrap ping supplied at the factory so that the wrapping material 46 will overlie a few inches of the factory-applied wrapping. Thereafter, the end of the preformed wrapping material 46 is led off the reel 45 through and between the heat chamber 47 and guide plate 49 of the heater assembly 42 and placed over the factory-wrapped portion of one of the pipe sections. In passing through the heating assembly 42 which is being supplied with heat, the thermoplastic responsive inner layer of the preformed Wrapping material 46 contacts the surface of the heating chamber 47 so as to be heated to an adhesive state. Thereafter, the C-shaped handles 55 are grasped and manually rotated in a direction causing the wrapping machine 15 to orbit the pipe 16 in a helical manner by virtue of the angularly disposed wheels and rollers towards the other of hte welded pipe sections.

The preformed wrapping material 36 is fed out from the heater assembly 42 in a direction to pass under the pressure applying assembly 33 so that sufiicient pressure can be applied to the material 46 to cause adhesion to the factory applied wrapping and subsequently to the ex posed pipe surfaces. Since the rollers 37 of the pressure applying assembly 33 are mounted in a resilient rockable manner, pressure is constantly maintained on the Wrapping material 46 during progress along the pipe in going from one diameter to a different diameter such as the difference in diameter between the factory wrapped pipe portions and the unwrapped pipe ends in the region of the weld joint.

After the exposed surfaces of the pipe sections 16a and 16b have been wrapped and the heater assembly 42 deactivated, the strip of wrapping material 46 is severed, for example, near the pipe 16, to permit removal of the machine 15. Next, the handles 23 of each releasable arm lock assembly 21 are disengaged from the frame members and the arms 25 are pivoted away from the wrapped pipe 16 to allow manual removal of the wrapping machine 15.

Referring finally to FIGS. and 11, the wrapping machine wraps the preformed material 46 about the abutting pipe sections 16a and 16b from a factory-wrapped portion 56 of one pipe section 1611 to a factory-wrapped portion 57 of the other pipe section 16b, the preformed material 46 being sufiiciently overlapped so as to form a reliable covering for the exposed pipe surfaces 58.

The invention provides a pipe wrapping machine which can readily be placed in position surrounding an exposed weld area to adhesively apply a protective felt thereto. The manner of applying the protective felt avoids the necessity for applying a hot tar of asphalt in the field and also allows any desired length of pipe to be wrapped.

Further, a single pipe wrapping machine is also adapted to wrap pipes of different diameters since the arm lock assemblies and pressure applying means are automatically adjustable to different diameter pipes. Additionally, since the respective wheels 29, 29' and 32 and pressure applying assembly are mounted within manually adjustable means, the pipe wrapping machine is further adapted to wrap a wider range of pipe diameter sizes.

The pipe wrapping machine is of a size and weight as to be easily transported and utilized manually. In addition, the machine is of a compact efiicient arrangement to-permit the necessary pipe wrapping and adhering operations to be performed quickly, easily and cleanly.

Having thus described the invention, it is not intended that it be so limited as changes may be readily made therein without departing from the scope of the invention. Accordingly, it is intended that the subject matter described above and shown in the drawings be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. A portable pipes wrapping machine for wrapping pipe manually comprising a frame defining a pipe receiving mouth for enveloping a pipe,

a locking means mounted on said frame for disposition across said pipe receiving mouth to retain a pipe therein,

means mounted on said frame for rotatably supporting said frame concentrically on a pipe,

a reel assembly mounted on said frame for rotatably supporting a roll of preformed wrapping material thereon for feeding of the wrapping material to the P P a heater assembly mounted on said frame for heating a strip of preformed wrapping material fed from said reel assembly, and

a pressure applying assembly mounted on said frame for pressing a strip of preformed wrapping material which has been heated in said heater assembly into adhesive engagement with a pipe disposed within said frame.

2. A portable pipe wrapping machine as set forth in claim 1 wherein said frame includes a pair of spaced U- shaped frame members.

3. A portable pipe wrapping machine as set forth in claim 2 wherein said frame further includes a pair of C- shaped handles secured to the extremities of said frame members whereby manual handling of said frame is further facilitated.

4. A portable pipe wrapping machine as set forth in claim 2 wherein said locking means includes an adjustable releasable arm lock assembly pivotally mounted on each of said frame members.

5. A portable pipe wrapping machine as set forth in claim 4 wherein each of said releasable arm lock assembly includes a first arm having means thereon for insertion in said frame member to lock said first arm to said frame member, a second arm disposed across said mouth of said frame member, and a tension spring means secured intermediately of said first and second arm for biasing said second arm towards said first arm whereby said pipe wrapping machine can be mounted on different sized pipes.

6. A portable pipe wrapping machine as set forth in claim 1 wherein said means for rotatably supporting said frame includes a plurality of rotatable elements angularly disposed in relation to said frame whereby said frame can be orbited about a confined pipe in helical manner.

- 7. A portable wrapping machine as set forth in claim 2 wherein each of said frame members includes a pluralityof rotatable elements angularly disposed in relation to said frame members for helical orbiting of a confined pipe, said rotatable elements being disposed at the points of a triangle for contacting a confined pipe at least at three points.

8. A portable pipe wrapping machine as set forth in claim 1 wherein said heater assembly includes a heating chamber for heating one side of the strip of preformed wrapping material, a guide plate mounted on said heating chamber to define a passageway therewith for guiding the strip of preformed wrapping material therethrough, and a heat source means for heating said heating chamber interiorly.

9. A portable pipe wrapping machine as set forth in claim 2 wherein said pressure applying means is mounted on one of said frame members, in angular relation there- References Cited to.

10. A portable pipe wrapping machine as set forth in UNITED STATES PATENTS claim 9 wherein said pressure applying means includes a 2,011,172 3/1935 C l t 1, 156 195 shaft pivotally secured to said one of said frame members, 5 2,471,530 5/1949 P l r 1 156 392 a first pair of rollers rotatably mounted on said shaft, 3,126,30 3/1964 herm 156-392 a bar means pivotally secured on said shaft, a second pair of rollers mounted on one end of said bar in spaced rela- FOREIGN PATENTS tion to said first pair of rollers, and a spring means se- 1,027,047 4/1966 Great Britain cured to the other end of said bar and said frame for 10 biasing said second pair of rollers inwardly of said frame EARL M BERGERT Primar Examiner whereby said second pair of rollers constantly maintains y a pressure applying force on said wrapping material with HOAG, Assistant Examine! varying sized pipe sections.

11. A portable pipe wrapping machine as set forth in 15 US. Cl. X.R. claim 10 wherein said second pair of rollers is rotatably 156--468, 486, 499 mounted in a rockable manner. 

